Blog for Zipline Attraction in the Smoky Mountains
Located in Pigeon Forge, TN and near Gatlinburg and Sevierville.
Glow-In-The-Dark Critters
By Ross Bodhi Ogle
Posted on May 2, 2023
It's no news flash that some animals are able to glow in the dark. Fireflies are a great example of this. In fact, many of you may already be familiar with the synchronous fireflies of the Elkmont section of Great Smoky Mountains National Park, which collectively begin and end their blinking spells in unison, and only for a brief window of time in early summer.
But those aren't the only glow-in-the-dark creatures that inhabit the park. A recent study has shown that salamanders are also cable of this trait, which is known in the scientific world as “biofluorescence” (or sometimes you'll hear “bioluminescence”).
Three years ago, a team of researchers at St. Cloud State University in Minnesota observed populations of frogs, salamanders and newts under blue and ultraviolet lights and discovered that every one of the amphibians was capable of biofluorescing. Several salamander species showed particularly striking glow patterns in response to blue light.
Following up on that study, two other biologists recently studied the biofluorescence of the southern gray-cheeked salamander, a species found only in the Great Smoky Mountains of Tennessee as well as some high-elevation areas of Western North Carolina. These “sallies” were exposed to blue wavelengths of light and then photographed in a controlled dark environment.
The findings showed that both the males and females exhibit a dull green glow across their entire bodies, although it's not noticeable under normal, daytime viewing conditions. But those sallies do absorb blue light energy from the spectrum and then re-emit it at a lower wavelength as a green shade.
As so often occurs in nature, the males of the species display more prominent glow patterns on their bodies, most notably a starry-sky pattern on their stomachs, from the tip of the tail all the way to the throat and often down to the digits of their feet. The researchers believe that these patterns developed as a way for males to attract mates - again, a very common theme in nature. When the males go courting, they put out pheromones and do a choreographed form of foot dancing. The fact that their feet are glowing helps them gain even more attention. The female doesn't show that same degree of speckling.
Some biologists believe that amphibian biofluorescence could be an evolutionary holdover. As different colors of light are filtered out as sunlight passes through the canopies of trees, only particular blue wavelengths reach the salamanders on the forest floor. This would also explain why some species of fish fluoresce as blue.
The Appalachian Mountains are among the oldest on earth, and over time, the Great Smoky Mountains developed a broad range of elevations as well as highly oxygenated streams and an abundance of microhabitats and rainfall. This helps explain, in part, why the Smokies have such a high number of salamander species. In fact, the Smokies have been described as the “salamander capital of the world,” with at least 31 different species of that amphibian make their home there. They range from the inch-long pigmy salamander to the eastern hellbender, which can measure up to 29 inches, making it the largest salamander in North America.
So the next time you come visit our Pigeon Forge attraction to go zip lining in the Smokies, you can think about this as you fly from tree to tree and tower to tower under the rich canopy of our Smoky Mountain forest. Who knows what unusual things are happening down below, just because only certain wavelengths of light are getting filtered down to the forest floor? Maybe some critters down there soaking up that light, just waiting to show off their glow when the sun goes down.
